Door operator



March 18, 1952 I G. A. CURTIS DOOR OPERATOR Filed Aug. 31, 1948 3 Sheets-Sheet l INVENTOR.

BY V I2 I flrroe/vsys March 18, 1952 A, CURTIS 2,589,479

DOOR OPERATOR v Filed Aug. 51, 1948 3 Sheets-Sheet 2 JNVENTOR. Guy 4. 60477.5

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G. A. CURTIS DOOR OPERATOR March 18, 1952 3 Sheets-Sheet 5 Filed Aug. 51, 1948 IIIIIIIIIIIIIIIIIIII,

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Patented Mar. 18, 1952 UNITED STATES PATENT OFFICE DOOR OPERATOR Guy. A. Curtis, Cleveland Heights, Ohio, assignor to UnitedMS'tates Motors Corporation, Oshkosh, Wis.,, a corporationv of Wisconsin Application August 31, 1948, .Serial No: 46,956:

- 1 This inventionrelates: to:improvements; in door operators;. more. particularly power' driven operators for garagedoors of theoverheadl sliding type. Heretofore operators for this type of door have embodied. reversible motors which are more expensive than motors designedto turn: always in the same direction and; which. require somewhat complicated electrical circuits for their control.

The present'invention utilizes a motor which turns in oneidirection. only and anendless' chain the opposite runs of which are connected onerat a time to the door for moving it in opposite directions. The opening of the motor circuit is effected automatically as the door arrives at fully open or fully closed position.

One of the objects of the invention is-the simplification.v of door operatingmechanism of the character stated.

Another object i's'the provision of a door operating mechanism embodying a carriage which moves back and. forth in a given path when pushed by one or the: other'of the two run of an endless chain driven always in the-same direction.

Another object: is the provision of control means for automatically breaking the motor circuit as thedoor completes its movement in either the openin'g or closing operation.

A further object: is the provision of power driven door. operating. means which. will not interfere with manual operation of the door.

Still another object is the' provision of'means inconnection with power: operationto automatically lock the door at the-end of the door closing. operation, orrto unlock: it at the-begin- 1 Claiin. (Cl.. 268'59.)

ning of the door opening operation, which locking means is susceptible also'of manualoperation.

Other objects and features of I novelty will appear as I proceed with the description of that embodiment of the invention which, for the purposes of the presentapplication, I have-illustrated in the accompanyin drawings, inwhich Fig. l isa vertical sectional view of a garage door provided with my improved operating mechanism, and a diagramofthe motor-circuit and control circuits therefor, theparts being shown in the position which they occupy' at an intermediate point of the door closing movement.

Fig. 2. is; a fragmental View of the driven 1 sprocket wheel and cooperating chain withcthe parts in :the position which they occupy whenthe 2 Fig. 3 isa vertical sectional view. taken. sub;- stantially on the line 33 of Fig. 2. h

Fig. 4-is a perspective: view of. the. slidin carriage to which the door isconnectedv Fig. 5 is a fragmental elevational view of'the inner sideof the door in-closed position.

Fig. 6 is a cross-sectionalview of the. door-and its connection. to the power operator,- together with locking means, and- Fig. 7 is a perspectivefragmental-view-show ingthe lock' disassembled.

Referring. first to Fig. 1. orthedrawings; there is shown agarage door formedof several 6101' gated sections or panels I 0 hinged together horizontally and provided at-its sideedges withlaterallyprojecting; shoes ll running: intracks. each of which iscomposedof straight sections l 2.-and I3 and an interconnecting curvedzsection. I4;

In an overhead position beneath'the ceilingor roof l 5- of the garage there. is mountedaaeguide i6- extending rearwardly from. the-1 door opening of suitable cross-sectional shape, it. being shown in the present instance as a tubular'- element of square cross-section with a longitudinal slot ll along its bottom side. Near the two endsot the guide l6 shafts; l8- and I9 are journaled" insthe side wall 'of the guide, and'uponthese shafts between the two side walls; sprocket wheelsdu and Marc fixed. Anendless-chainZZ-runsover thesesprocket wheels;

Carriage .23 is mounted to SHdQYbEZCK=fiI1d forth within therguide. I6.- As i illustrated herein/the carriage 23 comprises two; members; 24' and 25 that are joined: together by a metal; strap 26- in which I are formed; a series of perforations: 21 that are adapted to take the shanks ofbo'lts 28. These bolts extend through spacing. washersw2 9=-and are screwed into threaded. openings in the-base portions ofmembers 24 and 25; Aibracket 30: extends downwardlyfrom-strap*26; and. to-it there is pivoted a link 3-l which is connected with'the uppermost'section M of thedoora By: selecting the holes 21; members, 24 and-25 may be. spaced different distances from: bracket 30 =for adjust.- ment purposes. As the carriage 2:3 -movesrback and forth in guide 'I 6 thed'oor slidesiup and down along its track I 2,1 3, |4,.its two. extrem'ez-posiitions being. indicated-by brokenlines Fig-.1

Sprocket. wheel. 21' is; an idler." Wheel,"vv whilev sprocket wheel 20 is driven; by a pulley 23-. keyed to shaft I8 outside the'guide. 16; A1 belt-.34 runs over pulley 33 and over asmall;- pulley;- 9 fixed upon the shaft of a non-reversible: back geared electricsmotor' 35.

The carriage: member 24 is provided? with-:a

pair of projections 36 spaced apart suficiently to permit the lower run of chain 22 to pass between them. At the upper side of carriage member 25 there are two similar projections 31 between which the upper run of the chain may pass. 38

is a pin welded or otherwise fixed to chain 22 and extending transversely thereof, the pin being longer than the space between the two projection 36 or 31, as shown in Fig. 3. At the opposite point of the chain, that is at the maximum possible distance along the chain from pin 38 there is another pin 39 which may be similar to pin 38, except that it must be short enough to pass between the two projections 36 or the similar projections 31. When pin 38 i traveling in the upper run of the chain it engages the projections 31 and causes the carriage to travel toward the right. When it is traveling in the lower run of the chain it engages the projections 36 and pushes the carriage toward the left. When the carriage reaches either of the extreme positions indicated by broken lines in Fig. 1, pin 38 moves in a semicircle around the sprocket Wheel 20 or 2|, as the case may be, thereby disengaging itself from the projections 36 or 3'! and moving into the opposite run of the chain. The adjustments of the carriage with respect to the bracket 36 are such that at the times when the pin 38 leaves the projections on the carriage the door is either fully open or fully closed.

The casing of an electric switch of the microswitch type is illustrated at 4|. Projecting downward from this casing is a plunger 42 biased downwardly and toward switch closing position.

. An actuating arm 43 is hinged at 44 to casing 4|.

When either of the pins 38 and 39, in traveling upwardly around sprocket 2|] engages arm 43, that arm swings counterclockwise through a 'small angle, lifting the plunger 42 and opening the switch; This action results in stopping the motor by means of electrical connections which will now be described.

A 110 volt supply line is indicated at 58 and The primary coil of a step-down transformer 52 is connected into this circuit. The secondary coil of the transformer is connected into one side 53, 53' of a low voltage line which runs to an electromagnet 54, a return conductor 55 being connected to the other end of the magnet coil.

Conductors 53 and 55 maybe joined electrically by a suitable switch 56 which is biased toward open position.. The switch 56 may be a manual- 1y operated push-button or any other type of switch which tends to open when not held closed. When electromagnet 54 is energized by the closing of switch 56, an armature 57 is drawn into circuit bridged across the terminals of the secondary coil of the transformer 52, which consists of conductor 53' going to the magnet coil,

a short length of conductor 55, a conductor 62 leading to a contact 63, an armature 64 held in operative relation with contact 63 by the force of the magnet when energized, a conductor 65 leading to switch 4| and a return conductor 66 .back to the opposite side of the secondary coil of the transformer. I 7

When the door is closed the link 3| stands at an angle of about 45. Therefore, when the door keeper 15. by any suitable means adapted for actuation by matically on power operation of the door and' manually on manual operation. In the illustrated embodiment this locking means comprises a metal guide 18 secured to the top of the door, in which a bolt II is mounted to slide. This bolt is biased toward locking position by a tension spring 12 that is attached at its ends to posts 13 and I4 projecting upwardly from the guide and bolt respectively. This spring tends to hold the forward end of the bolt in engagement with a metal keeper 15 in the door frame, and also to cause the bolt to snap into the keeper when the door is closed.

At the rear end of the bolt there is a slot 16 which receives a pin Tl carried at one end of link 3|, by which the bolt is pulled out of its keeper when the carriage starts its travel toward the left. Hence the door is locked automatically when it moves into closed position and is un-v starts on the door opening movement.

In order that the door may be unlocked manually in the event that the electric operator fails to function for lack of current or otherwise, I provide a manual actuator for bolt 66 which may take the form herein illustrated. In this embodiment a bell crank lever 18 is pivoted to the door at E9. In the upright arm of this lever there is a slot 88 which receives pin Tl. From the horizontal arm of the lever a cable 8| extends downwardly along the inner wall of the door through a ring guide 82. Its lower end is eccentrically attached to a round bar 83 which projects through the door and is provided on the forward side thereof with handles 84 by means of which it may be turned to exert a pull on cable 8| and thereby to tilt bell crank 18 and withdraw the bolt from engagement with its Bar 83 may be locked against rotation a key 85.

Operation. Assuming, that the carriage 23 is in the broken line position at the left end of the guide |6, which is the same as the full line position of Fig. 2, the door being then fully open and the pin 38 occupying the dotted lineposition of Fig. 2 in which the switch 4| is open, and assuming that the operator wishes to set the mechanism into operation for closing the door, he may close switch 5'3 momentarily by manual actuation or throughthe intermediacy of an electrical impulse set in motion by any desired means. This will energize magnet 54, causing armatures 51 and 64 to engage contacts 58 and 63 respectively. The motor circuit is thereby completed and the motor starts to turn the sprocket wheel 28 clockwise. Pin 38 immediately 'moves upwardly out of engagement with actuating arm 43, which permits that arm to swing downwardly through an angle suflicient to permit plunger 42 to descend and cause closing of be permitted to open without affecting the motor circuit. As the chain travels due to rotation of sprocket wheel 20, pin 36 moves from the dotted line position of Fig. 2 to the full line position of that figure, when it engages the projections 31 and pushes carriage 23 toward the right, and the carriage working through strap 26, bracket 30 and link 3| pushes the door to the right and downward, as viewed in Fig. 1. This continues until the carriage reaches the position of Fig. 6, when the bolt H snaps into the keeper i5. Then pin 38, by turning around sprocket 2|, moves downwardly in an are out of engagement with projections 31'. At the same time that pin 38 reaches the level of shaft l9, pin 39 moves upwardly around sprocket wheel into engagement with switch actuating arm 43, thereby open ing the control circuit, deenergizing the magnet 54 and breaking the motor circuit at the point 51, 58. Thus the chain movement comes to a stop. In installing the door some adjustment of the strap 26 relative to the carriage 23 may be necessary in order to insure full closing of the or until pin 39 clears actuating arm 43, closingthe holding circuit. Shortly thereafter the pin 38 will strike the projections 36 and the carriage 23 will move toward the left, causing the link 3| to first pull out latch bolt II and then raise the door. The chain movement and the consequent carriage movement continue until the pin 38 engages actuating arm 43 and again brings about the opening of the motor circuit.

In case anything should happen which would prevent power operation of the door mechanism when the door is closed and locked, it may be readily opened by hand. To accomplish this it is necessary merely to insert and turn key 85, after which the bar 83 may be turned to exert a downward pull on cable 8!, thereby turning bell crank lever 18 to withdraw bolt H. The

operator may then push the door upward and inl ward along the track l2, l4, 13. This causes carriage 23 to travel to the left without afiecting the chain 22 or the pins 33 and 39. The reverse operations will close the door and lock it.

Having thus described my invention, I claim: Door operating mechanism comprising a straight hollow guide, a pair of sprocket wheels disposed within said guide near the ends thereof, an electric motor for turning one of said sprocket wheels in a given direction only, an endless chain running over said sprocket wheels within said guide, a two-sectional carriage slidable in said guide, a projection on one section of said carriage adjacent one run of said chain, a projection on the other section of said carriage adjacent the other run of said chain, said projections being spaced apart a substantial distance longitudinally of said guide, means adjustably connecting said sections of the carriage for varying the spacing GUY A. CURTIS.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 520,827 Koss June 5, 1894 1,453,550 Fogal May 1, 1923 1,632,237 Lemon June 14, 1927 1,716,156 Tracy June 4, 1929 2,084,733 Kahlifi June 22, 1937 2,194,650 Foster Mar. 26, 1940 2,221,216 Greegor et al Nov. 12, 1940 

